This invention is directed to moving walkways and, more particularly, to accelerating and decelerating moving walkways that include a plurality of overlapping platforms.
In the past, a wide variety of moving walkways, some with and some without accelerating and decelerating zones, have been proposed. One moving walkway that includes accelerating and decelerating zones is described in U.S. Pat. No. 3,939,959, entitled "Accelerating and Decelerating Moving Walkway" by Phillip Dunstan et al. The accelerating and decelerating moving walkway described in U.S. Pat. No. 3,939,959 includes a plurality of interconnected overlapping platforms movable in a closed-loop, substantially planar, horizontal path of travel having lengthy sides joined by curved ends.
The platforms described in U.S. Pat. No. 3,939,959 have generally planar upper and lower surfaces with the exception that the rear edge tapers to a featheredge. In other words, the platforms have a trapezoidal longitudinal cross-sectional configuration. The upper surface of each platform is combed and meshes with the combed bottom surface of a rotatable plate pinned to the bottom surface of the preceding platform, near its rear edge. Although the accelerating and decelerating walkway described in U.S. Pat. No. 3,939,959 (and especially the apparatus for controlling the acceleration and deceleration of the moving walkway) is a significant advance in the art, the disclosed platform design is not completely adequate in all environments. For example, in constant speed zones, where platform overlap is at a minimum, the upper surfaces of adjacent platforms do not lie in substantially the same plane. Rather, in the constant speed zones, the upper surfaces have a height variation equal to the thickness of one platform plus a rotatable plate. Although the tapered trailing edge of the platforms provides a transitional surface between the irregular upper surfaces of adjacent platforms, the transition is somewhat abrupt. As a result, passengers who change position on the moving walkway face a stumbling hazard.
In addition to the foregoing disadvantage, the way the rotatable plates are attached to the platforms of the walkway described in U.S. Pat. No. 3,939,959, is such that regions in which pinching or catching can occur are created. More specifically, because a platform and is related rotatable plate are pinned, the rotatable plates are free to rotate relative to the platforms, whereby the upper surfaces of the plates, which are combed, can become misaligned with the upper surfaces of their related platforms, which are also combed. This comb misalignment creates regions wherein pinching or catching can occur. A similar problem exists at entrance and exit comb plates, where passengers board and alight from the walkway. More specifically, entrance and exit comb plates overlie the platforms and mesh with the combed upper surfaces of the platforms. A misaligned rotatable plate will also be misaligned with the entrance and exit comb plates. As a result of this misalignment, the potential for pinching and catching passengers or their clothing exists. In addition, misalignment of a rotatable plate could prevent the rotatable plate from meshing with an exit comb plate, resulting in equipment failure.
Another disadvantage of the platform mechanism described in U.S. Pat. No. 3,939,959 relates to the relatively large turning radius required to change the direction of the moving platforms. More specifically, U.S. Pat. No. 3,939,959 discloses a track for guiding wheels located at the front edge of each platform around a semicircular path in the regions where platform direction changes take place. As the platforms change direction, the rotatable plates rotate relative to their respective platforms. Because of the way the plates rotate, and because platform overlap is at a maximum in the change of direction regions, a large turning radius is needed in order to avoid interference between adjacent, stacked platforms. Because a large turning radius is required, the entire closed-loop, accelerating and decelerating moving walkway described in U.S. Pat. No. 3,939,959 can only be installed in relatively wide corridors.
Therefore, it is an object of this invention to provide a new and improved accelerating and decelerating moving walkway.
It is another object of this invention to provide an accelerating and decelerating moving walkway having a minimal amount of upper surface irregularity.
It is a further object of this invention to provide a combed surface, overlapping platform, accelerating and decelerating moving walkway designed such that lateral misalignment of the platforms is prevented in regions where passengers or freight are transported.
It is a still further object of this invention to provide an accelerating and decelerating moving walkway having a substantially flat, continuous upper surface and the ability to change directions, particularly reverse directions, in a minimal amount of horizontal space.
It is yet another object of this invention to provide a new and improved accelerating and decelerating moving walkway that is suitable for being entirely installed in relatively narrow corridors.